CN111904672A

CN111904672A - Intervertebral fusion cage

Info

Publication number: CN111904672A
Application number: CN202010920579.9A
Authority: CN
Inventors: 郝晓艳
Original assignee: Individual
Current assignee: Individual
Priority date: 2020-09-04
Filing date: 2020-09-04
Publication date: 2020-11-10

Abstract

The invention provides an interbody fusion cage which is of a combined structure and comprises a far-side supporting block (1), a near-side supporting block (3), a connecting rod (2) and a locking nut (4). The distal and proximal support blocks are adapted to be oppositely disposed between the endplate edges of two adjacent vertebral bodies. One end of the connecting rod is fixedly connected with the middle part of the far-side supporting block, and the other end of the connecting rod is provided with a thread matched with the locking nut. The through hole that is used for supplying the tip of connecting rod to pass is seted up in the middle part of nearly side supporting shoe, and lock nut is located the one side that the nearly side supporting shoe is kept away from distal side supporting shoe for with nearly side supporting shoe and connecting rod fastening connection. The interbody fusion cage provided by the invention can provide a larger bone grafting area, is not easy to subside, and is beneficial to improving the operation effect.

Description

Intervertebral fusion cage

Technical Field

The invention relates to the technical field of medical instruments, in particular to an interbody fusion cage.

Background

The intervertebral Cage, also called Cage, is a container for bone and bone substitute material particles. Some operations require fusion of adjacent vertebral bodies by implanting bone or artificial bone into the vertebral body space, and after a period of time, the two vertebral bodies grow into a whole. If the intervertebral space only implants granular bones or artificial bones, no mechanical supporting force exists, the intervertebral space height cannot be maintained, a lot of problems are brought, the operation effect is influenced, and therefore the bones are placed into the fusion cage and then are stuffed into the intervertebral space, and the fusion cage is used as a supporting body while being used as a container to maintain the intervertebral space height.

The current intervertebral fusion device mainly has the following defects: the bone grafting area is small, and the bone grafting amount and the fusion rate are influenced; subsidence easily occurs, and the intervertebral height and the lordotic angle are lost due to the subsidence of the vertebral body, so that the operation effect is influenced. Therefore, how to improve the intervertebral fusion device to improve the operation effect becomes a technical problem to be solved by those skilled in the art.

Disclosure of Invention

In view of this, the present invention provides an intervertebral fusion cage, which can provide a larger bone grafting area, is not prone to subsidence, and is beneficial to improving the operation effect.

In order to achieve the purpose, the invention provides the following technical scheme:

an interbody cage of modular construction comprising a distal support block, a proximal support block, a connecting rod, and a locking nut, the distal support block and the proximal support block for relative disposition between endplate edges of two adjacent vertebral bodies; one end of the connecting rod is fixedly connected with the middle part of the far-side supporting block, and the other end of the connecting rod is provided with a thread matched with the locking nut; the middle part of the near side supporting block is provided with a through hole for the end part of the connecting rod to pass through, and the locking nut is positioned on one side of the near side supporting block, which is far away from the far side supporting block, and is used for fixedly connecting the near side supporting block and the connecting rod.

Optionally, in the above intervertebral cage, the connecting rod is in threaded connection with the distal support block.

Optionally, in the above intervertebral fusion device, one end of the connecting rod close to the locking nut is cone-shaped, and the through hole has a taper hole portion matching with the cone-shaped end portion of the connecting rod.

Optionally, in the above intervertebral fusion device, the through hole is a counter bore, and the locking nut is located in a counter bore of the through hole.

Optionally, in the above intervertebral fusion device, a groove wall of the counter sink is provided with an internal thread matching with the external thread of the locking nut, and the pitch of the external thread of the locking nut is not equal to that of the internal thread of the locking nut.

Optionally, in the intervertebral fusion device, a groove for matching with a socket wrench is formed in one surface of the locking nut, which is far away from the distal supporting block.

Optionally, in the intervertebral fusion device, an accommodating groove that is communicated with the sinking groove of the through hole is formed beside the through hole in the near-side supporting block, an accommodating hole that is communicated with the surface of the near-side supporting block on the side close to the vertebral end plate is formed in a groove wall of the accommodating groove, a locking column that is nailed into the vertebral body is arranged in the accommodating hole, and one end of the locking column abuts against the locking nut.

Optionally, in the intervertebral fusion cage, the number of the through holes is two and the through holes are arranged up and down, and the accommodating groove and the accommodating hole which correspond to each other are arranged beside each through hole.

Optionally, in the above intervertebral fusion device, the upper and lower surfaces of the proximal supporting block opposite to the vertebral body end plate are provided with positioning protrusions.

An interbody cage of modular construction comprising a distal support block, a proximal support block, an advancement sleeve, a connecting rod, and a locking nut, the distal and proximal support blocks being adapted to be oppositely disposed between endplate edges of two adjacent vertebral bodies; one end of the connecting rod is hinged with the middle part of the far-side supporting block, and the other end of the connecting rod is provided with a thread matched with the locking nut; the pushing sleeve is sleeved on the connecting rod and is in threaded connection with the connecting rod, and the pushing sleeve is used for jacking the far-side supporting block to enable the far-side supporting block to rotate relative to the connecting rod; the middle part of the near side supporting block is provided with a through hole for the end part of the connecting rod to pass through, and the locking nut is positioned on one side of the near side supporting block, which is far away from the far side supporting block, and is used for fixedly connecting the near side supporting block and the connecting rod.

According to the technical scheme, in the interbody fusion cage provided by the invention, the far-side supporting block and the near-side supporting block are oppositely arranged between the edges of the end plates of two adjacent vertebral bodies and are combined through the connecting rod, during operation, the connecting rod and the far-side supporting block are assembled and are driven into an intervertebral space, the far-side supporting block is supported on the opposite side edges of the vertebral bodies, then bones are implanted into the intervertebral space, after the intervertebral space is filled with bones, the near-side supporting block is placed, the end part of the connecting rod is inserted into the through hole of the near-side supporting block, the near-side supporting block is supported on the near side edge of the vertebral body, and finally, the locking nut is screwed to enable.

Because the intervertebral fusion device adopts a combined structure, the whole occupied space is small, and the far-side supporting block and the near-side supporting block are positioned at the edge of a vertebral body, the intervertebral fusion device can provide a larger bone grafting area, and the bone substitute material is directly filled in an intervertebral space, and can be closely contacted with the intervertebral space no matter the shape of the upper endplate and the lower endplate, so the fusion time can be greatly shortened. Meanwhile, the edge of the vertebral body end plate has the strongest pressure bearing capacity, so the intervertebral fusion cage is not easy to subside, and is beneficial to improving the operation effect.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.

FIG. 1 is an elevation view of an intervertebral cage according to an embodiment of the invention;

FIG. 2 is a bottom view of FIG. 1;

FIG. 3 is a cross-sectional view of FIG. 1;

FIG. 4 is a schematic view of the distal support block 1 of FIG. 3;

fig. 5 is a schematic view of the connecting rod 2 of fig. 3;

FIG. 6 is a schematic view of the proximal support block 3 of FIG. 3;

FIG. 7 is a schematic view of the locking nut 4 of FIG. 3;

FIG. 8 is a cross-sectional view of FIG. 7;

FIG. 9 is a schematic view of an intervertebral cage according to an embodiment of the invention in three states of use;

FIG. 10 is a cross-sectional view of an intervertebral cage according to a second embodiment of the invention;

FIG. 11 is a bottom view of FIG. 10;

FIG. 12 is a schematic view of the proximal support block 3 of FIG. 10;

FIG. 13 is a bottom view of FIG. 12;

fig. 14 is a schematic view of a proximal support block 3 in the intervertebral cage according to the third embodiment of the invention;

FIG. 15 is an elevation view of an intervertebral cage according to a fourth embodiment of the invention;

FIG. 16 is a side view of an intervertebral cage according to a fourth embodiment of the invention (with the proximal support block 3 omitted);

fig. 17 is two structural diagrams of the connecting rod 2 in the intervertebral cage according to the fourth embodiment of the invention.

Labeled as:

1. a distal support block; 2. a connecting rod; 3. a proximal support block; 31. sinking a groove; 32. accommodating grooves; 33. a housing hole; 34. positioning the projection; 4. a locking nut; 5. a vertebral body; 6. a locking post; 7. the sleeve is advanced.

Detailed Description

For the purpose of facilitating understanding, the present invention will be further described with reference to the accompanying drawings.

Example one

Referring to fig. 1 to 3, fig. 1 is a front view of an intervertebral cage according to an embodiment of the present invention, fig. 2 is a bottom view of fig. 1, and fig. 3 is a sectional view of fig. 1. The intervertebral cage provided by the first embodiment of the invention is a combined structure and comprises a distal supporting block 1, a connecting rod 2, a proximal supporting block 3 and a locking nut 4, wherein the distal supporting block 1 and the proximal supporting block 3 are used for being oppositely arranged between the end plate edges of two adjacent vertebral bodies 5 (see figure 9); one end of the connecting rod 2 is fixedly connected with the middle part of the far-side supporting block 1, and the other end of the connecting rod is provided with a thread matched with the locking nut 4; the middle part of the near side supporting block 3 is provided with a through hole for the end part of the connecting rod 2 to pass through, and the locking nut 4 is positioned on one side of the near side supporting block 3 far away from the far side supporting block 1 and used for tightly connecting the near side supporting block 3 and the connecting rod 2.

During the operation, squeeze into intervertebral space to the distal side supporting shoe 1 and connecting rod 2 that assemble well earlier, let distal side supporting shoe 1 support at the 5 opposite side edges of centrum, then plant the bone in intervertebral space, fill up intervertebral space after, put into near side supporting shoe 3, insert the through-hole of near side supporting shoe 3 with the end of connecting rod 2 to support near side supporting shoe 3 at 5 near side edges of centrum, twist lock nut 4 at last and let connecting rod 2 and near side supporting shoe 3 fastening connection.

As can be seen from the above operation process, the interbody fusion cage of the present invention adopts a combined structure, the overall occupied space is small, and the distal support block 1 and the proximal support block 3 are located at the edge of the vertebral body 5, so that the interbody fusion cage can provide a large bone grafting area, and since the bone substitute material is directly packed into the intervertebral space, the bone substitute material can be in close contact with the vertebral space regardless of the shape of the upper and lower endplates, so that the fusion time can be greatly shortened. In addition, the edge of the vertebral body end plate has the strongest pressure bearing capacity, so the intervertebral fusion cage is not easy to subside, and is beneficial to improving the operation effect.

In this embodiment, the connecting rod 2 is in threaded connection with the distal support block 1. As shown in fig. 4 and 5, a threaded hole is opened in the middle of the distal support block 1, external threads are provided at both ends of the connecting rod 2, the external threads at the upper end in fig. 5 are used for matching with the threaded hole of the distal support block 1, and the external threads at the lower end are used for matching with the threaded hole of the locking nut 4. Of course, in other embodiments, the connecting rod 2 and the distal support block 1 may be connected by other connection methods such as a snap, or the two may be designed as an integral structure, that is, the connecting rod 2 and the distal support block 1 are integrally formed.

As shown in fig. 5 and 8, in order to facilitate assembly and achieve a stable effect, in the present embodiment, one end of the connecting rod 2 near the locking nut 4 is cone-shaped, and correspondingly, the threaded hole of the locking nut 4 is also cone-shaped. In order to prevent as much looseness as possible between the connecting rod 2 and the proximal support block 3, the through hole of the proximal support block 3 should have a tapered hole portion that fits the tapered end of the connecting rod 2.

The cone-shaped end of the connecting rod 2 can enable the port of the long and thin hose to be easily sleeved on the connecting rod, and the hose can be easily pulled out, so that in operation, in order to prevent difficulty in assembling the near side supporting block 3 and the connecting rod 2, the long and thin hose can be sleeved at the cone-shaped tail end thread of the connecting rod 2, then the other end of the hose can penetrate through the through hole of the near side supporting block 3, under the guiding effect of the hose, the near side supporting block 3 can be easily sleeved on the connecting rod 2, and finally the hose can be pulled out, and the locking nut 4 can be screwed on the connecting rod 2.

In order to avoid as much space as possible for the locking nut 4, the through-hole of the proximal support block 3 is preferably a countersunk hole, as shown in fig. 6, the through-hole of the proximal support block 3 having a countersunk groove 31 for receiving the locking nut 4, the locking nut 4 being located in the countersunk groove 31 when the locking nut 4 is screwed onto the connecting rod 2, as shown in fig. 3.

In order to improve the firmness, in the present embodiment, the groove wall of the counter sink 31 is provided with an internal thread which cooperates with the external thread of the locking nut 4. As shown in fig. 2 and 3, in the present embodiment, the locking nut 4 is an inner hexagonal nut, and since the threaded hole of the locking nut 4 occupies a large portion of the thickness, the recess for inserting the inner hexagonal wrench is usually shallow, and the shallow recess is not favorable for the inner hexagonal wrench to normally function.

In specific practical application, the locking nut 4 can be made of a material with slight toughness, and the thread pitches of the outer thread and the inner thread are designed to be slightly different, so that the locking nut 4 is tightly screwed, and the firmness of assembly is enhanced.

Fig. 9 shows three states of use of the intervertebral cage provided in this embodiment, and it can be seen that the placement positions of the distal support block 1 and the proximal support block 3 on the vertebral body 5 can be determined according to the specific approach scheme of the operation. It should be noted that the "distal" of the "distal support block" and the "proximal" of the "proximal support block" are relative to the incision site of the surgical approach, i.e., the "distal support block" is placed first and is located opposite the surgical incision, and the "proximal support block" is placed last and is located at the surgical incision site during the surgical procedure. It will be readily appreciated that the profile of the distal support block 1 and the proximal support block 3 should be designed according to the anatomy of the spine, for example, in the case of the left side of fig. 9, the proximal support block 3 should be designed according to the profile shown in fig. 2, i.e. the frontal profile is wedge-shaped, due to the difference in the anteroposterior inter-vertebral spacing.

Example two

Referring to fig. 10 to 13, fig. 10 is a sectional view of an intervertebral cage according to a second embodiment of the present invention, fig. 11 is a bottom view of fig. 10, fig. 12 is a schematic view of a proximal support block 3 of fig. 10, and fig. 13 is a bottom view of fig. 12. The difference between the second embodiment and the first embodiment is that the locking column 6 is added, so that the intervertebral cage itself can be used for stabilizing the vertebral body, and partial operation does not need to be performed in-line fixation like the traditional operation.

Specifically, in the present embodiment, the near-side supporting block 3 is provided with an accommodating groove 32 communicating with the sinking groove 31 of the through hole beside the through hole, as shown in fig. 13, a groove wall of the accommodating groove 32 is provided with an accommodating hole 33 communicating to a surface of the near-side supporting block 3 close to one side of the vertebral end plate, and the locking column 6 is provided in the accommodating hole 33 for being driven into the vertebral body.

During operation, before the proximal support block 3 is placed, the locking column 6 is hidden in the accommodating groove 32, a locking hole is drilled at a position of a few millimeters away from the edge of the vertebral body, the accommodating hole 33 is aligned with the locking hole after the proximal support block 3 is placed, then one part of the locking column 6 hidden in the accommodating groove 32 is pushed into the locking hole, the other part of the locking column is still left in the proximal support block 3, and finally the locking nut 4 is screwed in, as shown in fig. 10 and 11, the locking nut 4 is abutted against one end of the locking column 6 while the proximal support block 3 and the connecting rod 2 are fixed by the locking nut 4, so that the locking column is prevented from being withdrawn.

EXAMPLE III

For the condition that the height of the fusion cage is larger, for example, the cervical vertebra sub-total cut fusion cage, two connecting rods 2 are needed to be arranged to ensure the stability of the fusion cage, and on the basis of the second embodiment, the upper contact surface and the lower contact surface of the near side supporting block 3 are all needed to be provided with the locking columns 6 to ensure that people can feel relieved without being fixed in the titanium plate. Referring to fig. 13 and 14, the third embodiment differs from the second embodiment in that the proximal support block 3 has two through holes arranged up and down, and each through hole is provided with a corresponding receiving groove 32 and a corresponding receiving hole 33.

As shown in fig. 14, to prevent misalignment of the upper and lower locking posts 6 into the locking holes during implantation, a positioning protrusion 34 may be provided on the upper and lower surfaces of the proximal support block 3 opposite the vertebral endplates. During operation, a guide is used for making a groove in the corresponding part of the vertebra in advance, and the same guide is used for making an upper locking hole and a lower locking hole, so that the upper locking column 6 and the lower locking column 6 can be aligned to the locking holes as long as the positioning bulge 34 of the near side supporting block 3 is punched into the groove.

Example four

In specific practice, the lumbar vertebra posterior fusion cage is used most, but is also designed most difficultly, because the fusion cage needs to be placed in from the posterior margin of the vertebral body, the posterior margin of the lumbar vertebra is smaller than the anterior margin, the height of the fusion cage which can be directly placed in the anterior margin is not enough, so that the fusion cage is an important reason for the insufficient anterior bulge after the operation of the intervertebral space, and the requirement on the height of the anterior margin can be met, but the fusion cage cannot be directly placed in from the posterior margin. To this end, the fourth embodiment of the present invention provides an intervertebral fusion cage, which is based on the first embodiment, wherein the connecting rod 2 and the distal support block 1 are designed to be in a hinged connection, and a pushing sleeve 7 is added, as shown in fig. 15 and 16, the pushing sleeve 7 is sleeved on the connecting rod 2 and is in threaded connection with the connecting rod 2, and the pushing sleeve 7 is used for pressing the distal support block 1 to rotate relative to the connecting rod 2.

From the side view shown in fig. 16, the connecting rod 2 and the distal support block 1 can be relatively angled with the joint of the two as an axis, so that the overall thickness can be reduced firstly when the connecting rod and the distal support block are put in place, then the pushing sleeve 7 is screwed, and the distal support block 7 is gradually pushed to be perpendicular to the connecting rod 2 along with the advance of the pushing sleeve 7, so that the distal support block 1 meeting the requirement of the height of the front edge gap of the vertebral body can be smoothly put in from the rear edge gap.

To increase the stability, the present exemplary embodiment provides the end of the thrust sleeve 7 close to the distal support block 1 in the form of a flange. Fig. 17 shows two configurations of the connecting rod 2 capable of articulating with the distal support block 1, i.e. the articulating end of the connecting rod 2 with the distal support block 1 may be either spherical or rod-shaped.

As shown in fig. 16, in order to reduce the overall thickness as much as possible, the included angle between the connecting rod 2 and the distal support block 1 should be adjusted as small as possible, however, if the included angle is too small, the pushing sleeve 7 cannot be pushed into the included angle when moving forward to the distal support block 1, so that the distal support block 1 cannot be jacked up, for this reason, a hole may be provided below the hinge joint of the distal support block 1 and the connecting rod 2, a front threading is put in, the distal support block 1 is rotated by pulling a wire to increase the included angle with the connecting rod 2 during surgery, and the pushing sleeve 7 is operated to move forward when the included angle is large enough to allow the end of the pushing sleeve 7 to be pushed in.

The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to the embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims

1. An interbody cage, characterized in that it is of modular construction, comprising a distal support block (1), a proximal support block (3), a connecting rod (2) and a locking nut (4), said distal support block (1) and said proximal support block (3) being intended to be oppositely arranged between the endplate edges of two adjacent vertebral bodies; one end of the connecting rod (2) is fixedly connected with the middle part of the far-side supporting block (1), and the other end of the connecting rod is provided with a thread matched with the locking nut (4); the middle part of the near side supporting block (3) is provided with a through hole for the end part of the connecting rod (2) to pass through, and the locking nut (4) is positioned on one side of the near side supporting block (3) far away from the far side supporting block (1) and used for fixedly connecting the near side supporting block (3) and the connecting rod (2).

2. Intervertebral cage according to claim 1, characterized in that the connection rod (2) is screwed to the distal support block (1).

3. An intersomatic cage according to claim 1, characterized in that the end of the connecting rod (2) close to the locking nut (4) is cone-shaped and the through-hole has a conical hole portion which cooperates with the cone-shaped end of the connecting rod (2).

4. Intervertebral cage according to claim 1, characterized in that the through hole is a countersunk hole, the locking nut (4) being located in a countersunk groove (31) of the through hole.

5. The intersomatic cage according to claim 4, characterized in that the walls of the counter sink (31) are provided with an internal thread cooperating with the external thread of the locking nut (4), the pitch of the external thread of the locking nut (4) and the internal thread of the locking nut (4) being unequal.

6. The intersomatic cage according to claim 5, characterized in that the face of the locking nut (4) remote from the distal support block (1) is provided with a recess for cooperation with a socket wrench.

7. The intersomatic cage according to claim 4, wherein the proximal support block (3) is provided with a receiving groove (32) beside the through hole, the receiving groove (32) is communicated with a sunken groove (31) of the through hole, a receiving hole (33) is formed in the wall of the receiving groove (32) and is communicated with the surface of the proximal support block (3) close to the vertebral endplate, a locking column (6) for nailing into the vertebral body is arranged in the receiving hole (33), and one end of the locking column (6) abuts against the locking nut (4).

8. Intervertebral cage according to claim 7, characterized in that the number of through holes is two and arranged one above the other, beside each of which there are provided the housing slots (32) and the housing holes (33) respectively corresponding thereto.

9. The intersomatic cage according to claim 8, characterized in that the proximal support block (3) is provided with positioning projections (34) on both its upper and lower surfaces opposite the vertebral endplates.

10. An interbody cage, characterized in that it is of a modular construction, comprising a distal support block (1), a proximal support block (3), a thrust sleeve (7), a connecting rod (2) and a locking nut (4), said distal support block (1) and said proximal support block (3) being intended to be oppositely arranged between the endplate edges of two adjacent vertebral bodies; one end of the connecting rod (2) is hinged with the middle part of the far-side supporting block (1), and the other end of the connecting rod is provided with a thread matched with the locking nut (4); the pushing sleeve (7) is sleeved on the connecting rod (2) and is in threaded connection with the connecting rod (2), and the pushing sleeve (7) is used for jacking the far-side supporting block (1) to enable the far-side supporting block to rotate relative to the connecting rod (2); the middle part of the near side supporting block (3) is provided with a through hole for the end part of the connecting rod (2) to pass through, and the locking nut (4) is positioned on one side of the near side supporting block (3) far away from the far side supporting block (1) and used for fixedly connecting the near side supporting block (3) and the connecting rod (2).